Appendix G: Message Queuing and Internet Communication

  • Article

Applies To: Windows Server 2003 with SP1

This section provides information about:

  • The purposes of Message Queuing

  • How Message Queuing handles messages

  • Finding additional sources of information about Message Queuing

Purposes of Message Queuing 3.0

Message Queuing (MSMQ) is one of the optional components in Microsoft Windows Server 2003. Information about Message Queuing is presented here so you as an IT administrator can be aware of the potential capabilities for use within your organization’s network, if you determine that you will be installing Message Queuing.

Message Queuing 3.0, the version in products in the Microsoft Windows Server 2003 family, is a message queuing service that enables applications on different systems to communicate with each other. Message Queuing implements asynchronous communication by enabling applications to send messages to and receive messages from other applications that may be running on the same computer or on different computers connected by a network. With Message Queuing, these applications can communicate across the Internet and other heterogeneous networks, and with computers that might be temporarily offline.

Overview: Using Message Queuing in a Managed Environment

Applications can use Message Queuing to send messages and to continue running regardless of whether the receiving application is running or reachable over the network. To create a message, an application specifies the message fields or properties and supplies the field values. The application then issues an MSMQ application programming interface (API) call to send the message. The MSMQ queue manager (the designated server) transmits the message to the destination message queue. If the destination location is not connected to the network when the message is sent, the message queuing system stores the message at an interim location. The system forwards the message automatically when a connection is established.

To receive a message, an application issues an API call that reads the message from the queue. When an application receives a request message, it processes the request by reading the contents of the message and acting accordingly. If required, the receiving application can send a response message back to the original requester. While in transit between senders and receivers, MSMQ keeps messages in holding areas called queues. MSMQ queues protect messages from being lost in transit and provide a place to retrieve messages when the receivers are ready to receive them.

Message Queuing 3.0 provides support for sending messages over the Internet. This support includes referencing queues by URLs, sending and receiving XML-based messages that are formatted using Simple Object Access Protocol (SOAP), and providing security for HTTP messaging. MSMQ also provides support for Web farms and firewalls. For more information about sending messages over the Internet, refer to "Related Links," later in this section.

It is beyond the scope of this white paper to describe all aspects of maintaining appropriate levels of security in an organization running applications that communicate across the Internet. This section, however, provides overview information as well as suggestions for other sources of information about balancing your organization’s requirements for running Internet applications with your organization’s requirements for protection of networked assets.

Controlling Message Queuing to Prevent the Flow of Information to and from the Internet

Installing and Uninstalling Message Queuing

Message Queuing is not installed by default. However, if your organization has determined that MSMQ is an essential component of the business process, it can be installed as described in this subsection. Although MSMQ is highly configurable, it is beyond the scope of this white paper to describe all the configuration options available to you. If you will be using MSMQ, you can refer to the "Related Links" subsection following these procedures for more detailed information about deploying Message Queuing.

To Install or Uninstall Message Queuing

  1. Click Start, and then either click Control Panel, or point to Settings and then click Control Panel.

  2. Double-click Add or Remove Programs.

  3. Click Add/Remove Windows Components (on the left).

  4. In Windows Components, select Application Server, and then click Details.

  5. Click Message Queuing and do one of the following:

    • If Message Queuing is installed and you want to remove it, clear the check box for Message Queuing and complete the Message Queuing wizard.

    • If Message Queuing is not installed and you want to add it, select the check box for Message Queuing.

  6. If you are installing Message Queuing, select Details, select one or more of the options listed, and complete the Windows Components wizard.

Accessing the Operating System Help Documentation for Message Queuing

The operating system has Help documentation describing the use of Message Queuing. You can view this documentation from any computer that has Internet access (regardless of the operating system running on that computer), or from any server running a product in the Windows Server 2003 family.

To Access the Help Documentation for Message Queuing

Open Help for Windows Server 2003 by doing one of the following:

For more information about Message Queuing, see the following references: